It is the overall goal of this project to develop a number of different biochemical loci for studying the effects of exogenous perturbants. These systems include the control of DNA replication, recombination and repair; a variety of metabolic control points influencing folate metabolism, cell membrane and glycogen biosynthesis, specific membrane receptors and finally those differentiating cellular systems which can influence antibody diversity. The effects of viruses, transfecting or transforming DNA, nutritional states, heavy metals, chemotherapeutic agents, mutagens and carcinogens will be examined at some of these functional biochemical loci.